Setting The Gas In Accordance With The Nozzle; Pressure Method - Vaillant atmocraft Installation And Maintenance Instructions Manual

The permissible range for the connection flow pressure
is:
17.0 to 25.0 mbar - 2nd gas family (natural gases)
35.0 to 45.0 mbar - 3rd gas family (liquid gases)
Caution!
If the connection pressure is outside the quoted
range, the cause of the deviation should be
found and the fault should be rectified.
If no fault can be found no adjustments should
be made and the boiler must not be started up
and the responsible office of the gas supply
company must be informed.
• Turn the boiler off.
• Remove the pressure gauge and close the connection
pressure measuring connection (1) with the sealing
screw.

6.2.3 Setting the gas in accordance with the nozzle

pressure method

1
Fig. 6.2 Setting the nozzle pressure
Adjustment of the gas is only required after changing
over to liquid gas (B/P). The cover cap over the setting
screws must be removed for setting.
• Close the gas-cock in the main gas infeed line to the
boiler.
• Release the closing screw in the nozzle pressure
measuring connection (2), and connect a gas pressure
measuring instrument with a resolution of 0.1 mbar to
the nozzle pressure measuring on the gas distributor
pipe.
• Open the gas shut-off cock again.
• Start the boiler up in accordance with Chapter 6.
Installation and maintenance manual atmoCRAFT
2
Setting the 1st. stage
• Change the boiler over via the diagnosis point d.00 to
operation of the 1st stage.
• Adjust the nozzle pressure for part output 65% (1st
stage) using a screwdriver on the slotted screw.
Turning to the right (+) = nozzle pressure higher - more gas
Turning to the left (-) = nozzle pressure lower - less gas
Setting the 2nd. stage
• Change the boiler over, if necessary, via the diagnosis
point d.00 to operation of the 2nd stage (full output).
• Compare the nozzle pressure with the value in the
table in Chapter 6.2.4.
Note!
Turn only up to the set burner pressure. Turning
too far can lead to destruction of the pressure
regulator.
• First set the nozzle pressure for the nominal output
(2nd. stage) using an open-ended spanner SW 8 on the
hex nut (1). The setting screw (2) should be held
stationary with a screwdriver whilst doing this.
Turning to the right (+) = nozzle pressure higher - more gas
Turning to the left (-) = nozzle pressure lower - less gas
• Turn the boiler off.
• Close the gas-cock in the main gas infeed line to the boiler.
• Remove the gas pressure measuring instrument.
• Turn the screw tightly in the nozzle pressure
measuring connection on the gas distribution pipe.
• Change the boiler back over via the diagnosis point
d.00 to automatic operation.
Start-up 6
GB 27